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Reaction mechanisms for selective hydrogenation of aromatic hydrocarbons to cycloolefins and cycloalkanes over noble metal catalysts were studied at the molecular level. Reactive intermediates were identified by combining experimental IR and Raman spectroscopic measurements with DFT calculations and related to catalytic activity and selectivity differences. Improved catalyst formulations were developed. 

This work proves the feasibility of utilizing steady state and transient in situ/operando spectroscopy to extract mechanistic information that reduces and leads to robust kinetic models. It also opens new avenues to explore kinetics and mechanisms with charge transfer data in heterogeneous catalysis. 

The development of simple in situ spectrokinetic techniques to assess intermediate species nature and adsorption location can benefit catalytic studies by providing insights into the reasons for different catalysts performance and facilitate mechanistic proposals. 

We present results of a search for spin-independent dark matter-nucleus interactions in a $1{\mathrm{cm}}^2$by 1 mm thick (0.233 g) high-resolution silicon athermal phonon detector operated above ground. For interactions in the substrate, this detector achieves an rms baseline energy resolution of $361.5\left(4\right)\mathrm{m}\mathrm{eV}$(statistical error), the best for any athermal phonon detector to date. With an exposure of $0.233\mathrm{g}\times 12$hours, we place the most stringent constraints on dark matter masses between 44 and $87\mathrm{M}\mathrm{eV}/{\mathrm{c}}^2$, with the lowest unexplored cross section of $4\times {10}^{-32}{\mathrm{c}\mathrm{m}}^2$at $87\mathrm{M}\mathrm{eV}/{\mathrm{c}}^2$. We employ a conservative salting technique to reach the lowest dark matter mass ever probed via direct detection experiment. This constraint is enabled by two-channel rejection of low energy backgrounds that are coupled to individual sensors. 

With the proliferation of connected internet of things (IoT) devices, trusted communications between such devices is an increasing concern. While researchers have spent significant resources to address this challenge, most solutions impose significant energy, delay, and complexity overhead on energy-constrained IoT devices. In this paper, we first provide an overview of some of the techniques used to incorporate security and trust features into IoT devices. Then, we propose and demonstrate an innovative encryption approach for wireless IoT communications which is low-energy, low-complexity, and lowlatency. The proposed cryptography integrates the encryption into the RF front-end of a wireless transceiver and is energyefficient, making it suitable for real-time and energy-limited IoT connectivity applications. 

Abstract There is ample evidence for magnetic reconnection in the solar system, but it is a nontrivial task to visualize, to determine the proper approaches and frames to study, and in turn to elucidate the physical processes at work in reconnection regions from in-situ measurements of plasma particles and electromagnetic fields. Here an overview is given of a variety of single- and multi-spacecraft data analysis techniques that are key to revealing the context of in-situ observations of magnetic reconnection in space and for detecting and analyzing the diffusion regions where ions and/or electrons are demagnetized. We focus on recent advances in the era of the Magnetospheric Multiscale mission, which has made electron-scale, multi-point measurements of magnetic reconnection in and around Earth’s magnetosphere.